Interstitials

Interstitials are elements that lay themselves over the content of a page, most often as pop-ups: newsletter boxes, discount banners or prompts to install an app. The term covers everything from small, discreet bars to overlays that fill the entire screen, and that difference decides how they affect your SEO.

Google uses the term intrusive interstitials for pop-ups that push the content itself into the background, and has counted them as a negative signal on mobile since 2017. A user who clicks a search result and meets a wall of pop-ups instead of the answer has a poor experience, and that can cost rankings. Exceptions exist: cookie consent, age verification and other legally required notices do not count as intrusive, and neither do banners that occupy a modest part of the screen.

Google does not penalize pop-ups as such, however often that gets repeated. The assessment is about how much the overlay disturbs the first moment on the page, and in practice it turns on timing, size and how easily the overlay closes. A bar that slides into the bottom of the screen after a while of reading and a full-screen overlay that blocks the content the second it loads are two very different things in Google's eyes. The signal rarely weighs much on its own, though behavior tells the same story, which the guide to bounce rate covers from the other side.